Hey @Tracy-and-Steve0 I want to add to @Lindsey6's good advice. Don't let guests intimidate you. You are a business, and while your business is the people business, it doesn't mean being taken advantage of. This guest sounds like a bit of a bully and perhaps he's being a bit intimidating as a tactic to get what he wants. Right now, he wants to steal from you, don't let him.
You very simply tell the guest - I am submitting an alteration to the booking to change the guest count to 3. You mistakenly made the booking for only two guests. Do this in the message thread, and be prepared to say the same thing if he asks you about it. Don't engage in any why's, why nots, buts and ifs. The guest made a booking for two, you could very easily have turned him away but you did not, you are now just updating the booking to ensure that it's correct.
With regard to cable, you've already called your provider, but I would have told the guest - we don't have ESPN. We have X, Y, Z. The guest didn't specifically ask before hand, and it is not a reasonable expectation to think that "cable" equals various sports specialty channels. He did ask about wifi and you answered that.
If you get a negative review, then you'll reply to it with something like "my listing does not indicate specialty channels" or whatever. FUture guests will see a potentially negative review but will also see the professional manner in which you replied to it, and they'll figure it out.
One thing that is very hard for new/newish hosts to learn is that it's up to you to be the boss, not the guest. It takes time to develop that skill and it will come. I've been hosting for six years, and I still let myself get taken advantage of by some guests, but I am getting better at setting clear boundaries.